Stepanyuk L.M., stepaniuk@nas.gov.ua, https://orcid.org/0000-0001-5591-5169
Dovbush T.I., tetyana.dovbush1@gmail.com, https://orcid.org/0000-0002-3512-3313
Vysotsky O.B., alek.vysotsky@gmail.com, https://orcid.org/0000-0002-3542-4685
Baran A.M., baranandrew9@gmail.com, https://orcid.org/0000-0002-5326-8014
Kanunikova L.I., Kanunikova59@gmail.com, https://orcid.org/0000-0002-7530-969Х
M.P. Semenenko Institute of Geochemistry, Mineralogy and Ore Formation of the NAS of Ukraine, 34, Acad. Palladin Ave., Kyiv, Ukraine, 03142
https://doi.org/10.15407/gof.2025.46.056
Metavolcanites of acidic composition are quite common formations among the rocks of the crystalline complex of the Marmarosh massif — the Dilovetska, Bredetselska, Tulgesh series, etc. Due to weak metamorphic transformations, metamorphically in greenschist facies conditions, they are easily diagnosed in the field. This report presents the results of uranium-lead isotope dating (TIMS method) of multigrain samples of zircon crystals from the metagranite-porphyry of the Saulyak deposit (Rakhiv Mountains) and the porphyroid of the Perkalab stream (Chyvchyn Mountains). According to the upper section of the concordia regression line, the age of the metagranite-porphyry is 505 ± 25 Ma, the porphyroid — 482 ± 51 Ma. The weighted average age of the metagranite-porphyry by the isotopic ratio 207Pb/206Pb is 515.5 ± 4.3 Ma and the porphyroid — 474 ± 3.6 Ma.
Keywords: uranium-lead isotope method, zircon, metavolcanites, Marmarosh massif, Ukrainian Carpathians.
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